# Task 4: Confirm floor-mode hall POI visibility — Implementation Report

## Status
**DONE**

## Summary
Source inspection confirms floor mode already prevents hall POI hiding via distance/limit pruning. No code change required.

## Findings

### Step 1: Floor visibility tier inspection
Confirmed `getPoiVisibilityTier()` at `src/components/map/ThreeMap.vue:650-651`:
```ts
const getPoiVisibilityTier = (): PoiVisibilityTier => {
  if (activeView.value === 'floor') return 'full'
```

### Step 2: Visibility tier behavior analysis
When tier is `'full'`:
- `getPoiVisibilityLimit('full')` returns `Number.POSITIVE_INFINITY`.
- `getPoiScreenSpacing('full')` returns `0`.

### Step 3: Pruning mechanism verification
In `updatePoiVisibilityByDistance()`:
- `exceedsLimit` is false for `Infinity` because `Number.isFinite(Infinity)` is false.
- `isTooClose` is false when spacing is 0.
- `exhibition_hall` and `exhibition_hall_entrance` are in `corePoiCategories`.

### Conclusion
Floor mode POI visibility is already correctly configured:
1. Distance pruning is disabled.
2. Count pruning is disabled.
3. Hall POIs pass category checks.
4. Selected/focused POIs always show.

No code modification needed.

## Files Inspected
- `src/components/map/ThreeMap.vue`

## Commands Run
None required — source inspection confirms correct behavior.

## Commits Created
None — no code changes.

## Self-Review
- Floor mode already returns `'full'` visibility tier.
- `'full'` tier prevents both distance and count pruning.
- Hall POIs are included in `corePoiCategories`.
- Logic is correct and no defensive guard is needed.

## Concerns
None.